#define _CRT_SECURE_NO_WARNINGS 1
#include"stack.h"
void STInit(ST* ps)
{
	assert(ps);
	ps->a = NULL;
	ps->capacity = 0;
	ps->top = 0;
}
void STDestory(ST* ps)
{
	assert(ps);
	free(ps->a);
	ps->a = NULL;
	ps->capacity = 0;
	ps->top = 0;
}
void STpush(ST* ps, STDatatype x)
{
	assert(ps);
	if (ps->top == ps->capacity)
	{
		int newcapacity = ps->capacity == 0 ? 4 : ps->capacity * 2;
		STDatatype* temp = (STDatatype*)realloc(ps->a,newcapacity * sizeof(STDatatype));
		if (temp == NULL)
		{
			perror("realloc fail");
			return;
		}
		ps->a = temp;
		ps->capacity = newcapacity;

	}
	ps->a[ps->top] = x;
	ps->top++;
}
void STpop(ST* ps)
{
	assert(ps);
	assert(!STEmpty(ps));
	ps->top--;
}
STDatatype STTop(ST* ps)
{
	assert(ps);
	assert(!STEmpty(ps));
	return ps->a[ps->top-1];
}

int STSize(ST* ps)
{
	assert(ps);
	return ps->top;
}
bool STEmpty(ST* ps)
{
	assert(ps);
	return ps->top == 0;
}
